AI-generatedKythnos at a glance
- Best time
- Jun – Sep
- Warmest month
- Aug · 28°
- Warmest sea
- Aug · 24.9°
- Sunshine a year
- 2,790 h
- Rain a year
- 375 mm
- Climate
- Mediterranean
- Time zone
- UTC+2 / UTC+3
- Elevation
- 159 m
Climate in Kythnos
Kythnos has a Mediterranean climate with warm to hot, dry summers and mild, wetter winters. August is the warmest month with average highs of 28 °C, while January is the coolest at 14 °C. With around 2,790 hours of sunshine a year, Kythnos is sunny; July is the sunniest month with 11.9 hours a day.
Holiday weather through the year
Best time to visit Kythnos
The best time to visit Kythnos is from June to September. For a beach holiday – sea from 21 °C, warm and mostly dry – go from June to September. For sightseeing, day trips and hiking, conditions are most comfortable from March to July and from September to December. The wettest month is December with 79 mm of precipitation.
Kythnos through the seasons
How the weather changes over the seasons, with averages for each.
Kythnos in spring
Mar – May
Fair
- 16–22 °C by day
- Sea 17 °C
- 8.1 h of sun a day
- 12 rainy days in all
Kythnos in summer
Jun – Aug
Excellent
- 25–28 °C by day
- Sea 24 °C
- 11.4 h of sun a day
- 1 rainy day in all
Kythnos in autumn
Sep – Nov
Good
- 19–26 °C by day
- Sea 22 °C
- 7.0 h of sun a day
- 12 rainy days in all
Kythnos in winter
Dec – Feb
Poor
- 14–15 °C by day
- Sea 16 °C
- 3.9 h of sun a day
- 28 rainy days in all
Which month for what?
Beach & swimming
Jun – Sep
Sea from 21 °C, warm and mostly dry
Sightseeing & hiking
Mar – Jul, Sep – Dec
15–28 °C and not too much rain
Find your perfect month
Tell us what you like and we rate every month in Kythnos for you.
Your best months: July – September
Based on the climate averages; tap a month to see its details.
Weather in October
Weather in October
Holiday weather in October
Good
Best time to visit: June – September
Where to go in OctoberSea temperature in October
Good forSightseeing & walks
A typical day in October
- Morning, 08:00: about 17°
- Midday, 13:00: about 22°
- Afternoon, 16:00: about 22°
- Evening, 20:00: about 20°
- Night, 23:00: about 19°
07:2918:47
Pleasant evenings; a light layer can help.
Estimated from the average high and low: coolest around sunrise, warmest in mid-afternoon.
Light for photos in October
- Golden hour
- Morning 07:13–08:04 · evening 18:12–19:03
- Blue hour
- Morning 07:03–07:13 · evening 19:03–19:13
Golden hour: the sun between 4° below and 6° above the horizon; blue hour: 6° to 4° below it. Times for the 15th of the month; mountains and clouds shift the light.
October in Kythnos compared with home
Loading the climate at home …
Early or late October?
In October, daytime highs fall from about 24° at the start of the month to 20° at the end. The sea cools from 23° to 21°. The days get 1.1 h shorter.
| October | 1 Oct | 31 Oct |
|---|---|---|
| Daytime high | 24° | 20° |
| Night-time low | 18° | 15° |
| Sea | 23° | 21° |
| Daylight | 11.8 h | 10.7 h |
What is the weather like in Kythnos in October?
In October, Kythnos is warm: daytime highs average 22 °C, and nights cool down to about 17 °C. The sea averages 22.2 °C – refreshing for a swim. The sun shines for around 7.1 hours a day. Rain is rare: about 4 days bring 28 mm in total. It is often windy: on a typical day the wind peaks at around 33 km/h. All in all, October is a good month for a holiday in Kythnos.
More details for October
- Daylight
- 11 h 18 min07:29 – 18:47
- UV index
- 5 · moderateclear sky, noon (estimate)All months
- Muggy days
- 5 daysdew point 18 °C or moreAll months
- Wind
- 33 km/haverage daily peakAll months
- Cloud cover
- 32 %on averageAll months
- Hot days
- 0 days30 °C or moreAll months
- Time zone
- UTC+3offset from UTC
How the score comes together
- Temperatureweight 35 %50 %
- Seaweight 25 %74 %
- Sunshineweight 20 %68 %
- Few rainy daysweight 20 %100 %
Each factor is rated from 0 to 100 % and weighted for the travel style “Sun, sea & sand”.
What to pack in October
- Swimwear
- Sunscreen
- Windproof jacket
Compare two months in Kythnos
Pick two months to see how the weather differs. A tick marks the clearly better value; for temperatures it depends on your plans.
July has the better holiday weather in Kythnos: score 100 against 70. In July, days are 6 °C warmer than in October. The sea is 2 °C warmer in July. July has 4 fewer rainy days. The sun shines 5 hours longer a day in July.
| Month | October | July |
|---|---|---|
| Holiday weather score | 70 | 100better |
| Daytime high | 22° | 28° |
| Night-time low | 17° | 22° |
| Sea | 22.2° | 24.1° |
| Sunshine | 7.1 h | 11.9 hbetter |
| Rainy days | 4 | 0better |
| Rainfall | 28 mm | 1 mmbetter |
| Muggy days | 5better | 22 |
Based on the climate averages 1996–2025.
Kythnos month by month
The typical weather for every month at a glance.
14January14° · Sea 16° · 3.7 h
In January, Kythnos is cool: daytime highs average 14 °C, and nights cool down to about 9 °C. The sea averages 15.7 °C – swimming is only for the hardy. The sun is scarce, with only about 3.7 hours a day. Rain is frequent, with about 10 rainy days and 74 mm in total. It is often windy: on a typical day the wind peaks at around 37 km/h. All in all, January is not an ideal month for a holiday in Kythnos.
Kythnos in January19February14° · Sea 15° · 4.8 h
In February, Kythnos is cool: daytime highs average 14 °C, and nights cool down to about 9 °C. The sea averages 15.4 °C – swimming is only for the hardy. Expect around 4.8 hours of sunshine a day. Rain falls on about 9 days, adding up to 61 mm. It is often windy: on a typical day the wind peaks at around 37 km/h. All in all, February is not an ideal month for a holiday in Kythnos.
Kythnos in February28March16° · Sea 16° · 6.4 h
In March, Kythnos is cool: daytime highs average 16 °C, and nights cool down to about 11 °C. The sea averages 15.6 °C – swimming is only for the hardy. Expect around 6.4 hours of sunshine a day. Rain falls on about 7 days, adding up to 47 mm. It is often windy: on a typical day the wind peaks at around 34 km/h. All in all, March is not an ideal month for a holiday in Kythnos.
Kythnos in March38April18° · Sea 16° · 8.3 h
In April, Kythnos is mild: daytime highs average 18 °C, and nights cool down to about 13 °C. The sea averages 16.4 °C – swimming is only for the hardy. The sun shines for around 8.3 hours a day. Rain is rare: about 3 days bring 18 mm in total. It is often windy: on a typical day the wind peaks at around 31 km/h. All in all, April is not an ideal month for a holiday in Kythnos.
Kythnos in April61May22° · Sea 19° · 9.6 h
In May, Kythnos is warm: daytime highs average 22 °C, and nights cool down to about 16 °C. The sea averages 18.7 °C – bracing, so a wetsuit helps for longer swims. With around 9.6 hours of sunshine a day, there is plenty of sun. It hardly ever rains. All in all, May is a good month for a holiday in Kythnos.
Kythnos in May93June25° · Sea 22° · 11.3 h
In June, Kythnos is warm: daytime highs average 25 °C, and even at night it stays warm at around 20 °C. The sea averages 22.0 °C – refreshing for a swim. With around 11.3 hours of sunshine a day, there is plenty of sun. It hardly ever rains. All in all, June is an excellent month for a holiday in Kythnos.
Kythnos in June100July28° · Sea 24° · 11.9 h
In July, Kythnos is hot: daytime highs average 28 °C, and even at night it stays warm at around 22 °C. The sea averages 24.1 °C – pleasant for swimming. With around 11.9 hours of sunshine a day, there is plenty of sun. It hardly ever rains. The air is often humid and muggy. It is often windy: on a typical day the wind peaks at around 30 km/h. All in all, July is an excellent month for a holiday in Kythnos.
Kythnos in July100August28° · Sea 25° · 11.1 h
In August, Kythnos is hot: daytime highs average 28 °C, and even at night it stays warm at around 23 °C. The sea averages 24.9 °C – pleasant for swimming. With around 11.1 hours of sunshine a day, there is plenty of sun. It hardly ever rains. The air is often humid and muggy. It is often windy: on a typical day the wind peaks at around 32 km/h. All in all, August is an excellent month for a holiday in Kythnos.
Kythnos in August100September26° · Sea 24° · 9.1 h
In September, Kythnos is warm: daytime highs average 26 °C, and even at night it stays warm at around 20 °C. The sea averages 24.2 °C – pleasant for swimming. With around 9.1 hours of sunshine a day, there is plenty of sun. It hardly ever rains. It is often windy: on a typical day the wind peaks at around 31 km/h. All in all, September is an excellent month for a holiday in Kythnos.
Kythnos in September70October22° · Sea 22° · 7.1 h
In October, Kythnos is warm: daytime highs average 22 °C, and nights cool down to about 17 °C. The sea averages 22.2 °C – refreshing for a swim. The sun shines for around 7.1 hours a day. Rain is rare: about 4 days bring 28 mm in total. It is often windy: on a typical day the wind peaks at around 33 km/h. All in all, October is a good month for a holiday in Kythnos.
Kythnos in October31November19° · Sea 20° · 4.8 h
In November, Kythnos is mild: daytime highs average 19 °C, and nights cool down to about 14 °C. The sea averages 19.5 °C – bracing, so a wetsuit helps for longer swims. Expect around 4.8 hours of sunshine a day. Rain falls on about 7 days, adding up to 48 mm. It is often windy: on a typical day the wind peaks at around 34 km/h. All in all, November is not an ideal month for a holiday in Kythnos.
Kythnos in November13December15° · Sea 17° · 3.3 h
In December, Kythnos is cool: daytime highs average 15 °C, and nights cool down to about 11 °C. The sea averages 17.2 °C – bracing, so a wetsuit helps for longer swims. The sun is scarce, with only about 3.3 hours a day. Rain is frequent, with about 10 rainy days and 79 mm in total. It is often windy: on a typical day the wind peaks at around 37 km/h. All in all, December is not an ideal month for a holiday in Kythnos.
Kythnos in DecemberClimate in detail
Climate through the year
Long-term monthly averages. Tap a month to see its details.
Nights and sleep in Kythnos
How warm the nights get in each month, from the mean night-time low. Tap a month for details.
- Cool 8–15°
- Pleasant 15–20°
- Warm 20–24°
- muggy month (15+ muggy days)
PleasantOctober: nights around 17°. Ideal for sleeping, often with the window open. Muggy on about 5 days (dew point 18 °C or more).
The coolest nights are in January (9°), the warmest in August (23°). Tropical nights of 20 °C and more are the rule from June to September; then air conditioning or a fan helps you sleep. Nights are pleasant for sleeping (15 to 20 °C) in May and in October. It is muggy (dew point 18 °C or more) on about 78 days a year, mostly from July to August.
Temperatures through the year
Average daytime high, night-time low and sea temperature per month.
| Month | Score | Day | Night | Sea | Sun | Rain days | Rain mm |
|---|---|---|---|---|---|---|---|
| JanuaryJan | 14 | 14° | 9° | 15.7° | 3.7 h | 10 | 74 |
| FebruaryFeb | 19 | 14° | 9° | 15.4° | 4.8 h | 9 | 61 |
| MarchMar | 28 | 16° | 11° | 15.6° | 6.4 h | 7 | 47 |
| AprilApr | 38 | 18° | 13° | 16.4° | 8.3 h | 3 | 18 |
| MayMay | 61 | 22° | 16° | 18.7° | 9.6 h | 2 | 7 |
| JuneJun | 93 | 25° | 20° | 22.0° | 11.3 h | 1 | 3 |
| JulyJul | 100 | 28° | 22° | 24.1° | 11.9 h | 0 | 1 |
| AugustAug | 100 | 28° | 23° | 24.9° | 11.1 h | 0 | 2 |
| SeptemberSep | 100 | 26° | 20° | 24.2° | 9.1 h | 2 | 8 |
| OctoberOct | 70 | 22° | 17° | 22.2° | 7.1 h | 4 | 28 |
| NovemberNov | 31 | 19° | 14° | 19.5° | 4.8 h | 7 | 48 |
| DecemberDec | 13 | 15° | 11° | 17.2° | 3.3 h | 10 | 79 |
Climate averages 1996–2025 (sunshine partly WMO station normals 1991–2020), not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences
37.41° N, 24.43° E · 159 m · Europe/Athens
Sea temperature in Kythnos
Monthly sea surface temperature with the range of cooler and warmer years.
8 in 10 years: 20.8 – 23.3 °C
Swimming season: Jun – Oct
- cold
- fresh
- refreshing
- pleasant
- warm
- very warm
The sea temperature in Kythnos ranges from 15.4 °C in February to 24.9 °C in August. It is warm enough for a comfortable swim (20 °C and more) from June to October.
From October to March the sea is even warmer than the afternoon air. The sea temperature varies from year to year: in August, eight out of ten years were between 24.1 and 25.9 °C.
| Month | Average | Cool year | Warm year | Feels |
|---|---|---|---|---|
| JanuaryJan | 15.7° | 14.9° | 16.5° | cold |
| FebruaryFeb | 15.4° | 14.6° | 16.0° | cold |
| MarchMar | 15.6° | 14.9° | 16.2° | cold |
| AprilApr | 16.4° | 15.6° | 16.9° | cold |
| MayMay | 18.7° | 17.8° | 19.4° | fresh |
| JuneJun | 22.0° | 21.2° | 22.9° | refreshing |
| JulyJul | 24.1° | 23.3° | 24.8° | pleasant |
| AugustAug | 24.9° | 24.1° | 25.9° | pleasant |
| SeptemberSep | 24.2° | 23.0° | 24.9° | pleasant |
| OctoberOct | 22.2° | 20.8° | 23.3° | refreshing |
| NovemberNov | 19.5° | 18.3° | 21.2° | fresh |
| DecemberDec | 17.2° | 16.3° | 18.6° | fresh |
Sunshine hours in Kythnos
Average hours of bright sunshine per day, next to the length of the day. Tap a month to select it.
In October, the sun shines for about 7.1 of 11.3 hours of daylight in Kythnos, 63 % of the daylight hours.
Sunshine hours: estimated from radiation data (ERA5, 1996–2025) and calibrated against measured station values; no weather station is close enough here. Daylight is the time from sunrise to sunset on the 15th of the month.
Rain in Kythnos: rainy days and rainfall
A rainy day is a day with at least 1 mm of rain or snow; the amount is what falls in the whole month. Tap a month to select it.
In October, Kythnos has about 4 rainy days with 28 mm of rain in total.
UV index in Kythnos
How strong the sun is at noon, month by month, and how quickly unprotected skin burns.
- Clear-sky UV in October
- 5 · moderateAround midday seek shade; use sunscreen, a hat and sunglasses.
The sun is strongest in June (UV 10).
Minutes until sunburn in October
- Very fair skin
- about 30 min
- Fair skin
- about 35 min
- Light brown skin
- about 50 min
- Olive skin
- about 65 min
Rough guide for unprotected skin at noon under a clear sky; clouds lengthen the time, water, sand and snow shorten it. Sunscreen extends the time only partly.
Monthly values: clear-sky noon estimate from the sun's angle, ozone and altitude. UV today: Open-Meteo forecast.
Wind and clouds in Kythnos
How breezy and how cloudy Kythnos is through the year. Tap a month to select it on the whole page.
Wind
Typical daily peak of the wind in km/h: what the afternoon breeze usually reaches, not the gusts.
In October, the wind in Kythnos typically peaks at 33 km/h during the day: Beaufort 5, fresh breeze.
Breezy months for windsurfing and kiting
From Beaufort 4 (20 km/h) the daily breeze is usually enough for windsurfing and often for kiting, and here it is that strong all year.
Clouds
Average share of the sky covered by cloud, day and night.
In October, cloud covers on average 32 % of the sky over Kythnos: mostly sunny, with about 7.1 hours of sunshine a day.
Wind: mean daily maximum of the hourly wind 10 m above ground (ERA5, 1996–2025). Gusts are stronger, and the model grid of about 28 km smooths out local effects such as capes and valley winds. Clouds: mean total cloud cover of all layers over day and night (ERA5, 1996–2025). Thin high cloud counts as cover even when the sun still shines through.
Heat and humidity in Kythnos
How often the day gets hot in Kythnos (30 °C and more), and in which months heat and humidity come together. Tap a month to select it.
Heat calendar
- pleasant
- some hot or muggy days
- often muggy
- often hot
- hot and muggy
In October, Kythnos has about 0 hot days, with an average daytime high of 22 °C: some hot or muggy days. Single hot or muggy days are possible; a hat and water bottle are enough.
Hot days reach at least 30 °C; a month counts as muggy when the mean dew point reaches 18 °C on at least 15 days. Averages from ERA5 and ERA5-Land, 1996–2025. Muggy nights through the year
Planning a trip to Kythnos
Weather for your travel dates
Pick your arrival and length of stay, and we sum up the weather to expect.
Kythnos in the school holidays
How the weather suits the usual holiday periods. Dates vary by school and region, so each holiday uses the months it usually falls in.
Kythnos has its best school-holiday weather during the summer holidays (score 100) and its weakest during the Christmas holidays (score 14).
- 35
Easter holidays
Mar – Apr
Poor
- 17 °C by day
- Sea 16 °C
- 7.7 h of sun a day
- 4 rainy days a month
Good for: Sightseeing & walks
- 67
May half-term
May – Jun
Good
- 22 °C by day
- Sea 19 °C
- 9.9 h of sun a day
- 2 rainy days a month
Good for: Sightseeing & walks
- 100
Summer holidays
Jul – Aug
ExcellentBest holidays
- 28 °C by day
- Sea 25 °C
- 11.4 h of sun a day
- 0 rainy days a month
Good for: Beach & swimming
- 70
October half-term
Oct
Good
- 22 °C by day
- Sea 22 °C
- 7.1 h of sun a day
- 4 rainy days a month
Good for: Sightseeing & walks
- 14
Christmas holidays
Dec – Jan
Poor
- 14 °C by day
- Sea 16 °C
- 3.5 h of sun a day
- 10 rainy days a month
Based on the climate averages 1996–2025.
Getting there
Flying from
- Nonstop flight
- about 3 h 30 min
- Distance
- 2,500 km
- Time zone
- UTC+3
- Jet lag
- Hardly any (under 3 h)
Estimated from the straight-line distance: 30 minutes for take-off and landing plus 830 km/h cruising speed.
Compare & alternatives
Kythnos compared
Put Kythnos side by side with another destination.
Kythnos vs Kea
In October Kythnos has the better holiday weather (score 70 vs 55). During the day Kea is 2 °C cooler than Kythnos. The sea is about equally warm. Kea gets one hour less sunshine a day.
| in October | Kythnos | Kea |
|---|---|---|
| Holiday weather score | 70 | 55 |
| Daytime high | 22° | 20° |
| Sea | 22° | 22° |
| Sunshine | 7 h | 6 h |
| Rainy days | 4 | 4 |
| Best time | Jun – Sep | Jul – Sep |
Through the year
Greece in October: the best places
In October, Kythnos ranks 24 among the 31 nearest destinations in this country.
- Athens24°23°91
- 2Piraeus24°23°91
- 3Tolón25°23°85
- 4Palaio Faliro24°23°84
- 5Elefsina24°23°84
- 6Thebes23°84
- 7Salamis Island24°23°83
- 8Spetses24°23°83
- 24KythnosThis page22°22°70
Near Kythnos
Other destinations close by.
Places with a climate like Kythnos
Destinations whose weather through the year is closest to Kythnos's – good alternatives.
Frequently asked questions about Kythnos
When is the best time to visit Kythnos?
The best time to visit Kythnos is from June to September. That is when the holiday weather score, which combines temperature, sea, sunshine and rain, is highest.
How warm is the sea in Kythnos?
The sea temperature in Kythnos ranges from 15.4 °C in February to 24.9 °C in August. It is warm enough for a comfortable swim (20 °C and more) from June to October.
Can you swim in Kythnos in October?
Yes. In October the sea averages 22.2 °C – refreshing for a swim.
What is the warmest month in Kythnos?
August is the warmest month, with average highs of 28 °C and nights around 23 °C. January is the coolest month at 14 °C.
When does it rain most in Kythnos?
The wettest month is December with 79 mm of precipitation. The driest month is July with 1 mm.
How many hours of sunshine does Kythnos get?
Kythnos gets around 2,790 hours of sunshine a year. The sunniest month is July with 11.9 hours a day; in December there are 3.3 hours a day.
What time zone is Kythnos in?
Kythnos is on UTC+2 in January and UTC+3 in July.
How long is the flight from London to Kythnos?
A nonstop flight from London to Kythnos takes about 3 h 30 min, for a straight-line distance of about 2,500 km.
Which school holidays are best for Kythnos?
Kythnos has its best school-holiday weather during the summer holidays (score 100) and its weakest during the Christmas holidays (score 14). Holiday ratings (0–100): Easter holidays 35, May half-term 67, summer holidays 100, October half-term 70, Christmas holidays 14.